From 89eb1906a9530ef694b2a5817c9498997722754f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 1 Jun 2018 09:03:08 -0700 Subject: iomap: add an iomap-based bmap implementation This adds a simple iomap-based implementation of the legacy ->bmap interface. Note that we can't easily add checks for rt or reflink files, so these will have to remain in the callers. This interface just needs to die.. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/iomap.c | 34 ++++++++++++++++++++++++++++++++++ include/linux/iomap.h | 3 +++ 2 files changed, 37 insertions(+) diff --git a/fs/iomap.c b/fs/iomap.c index 74cdf8b5bbb0..b0bc928672af 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -1307,3 +1307,37 @@ int iomap_swapfile_activate(struct swap_info_struct *sis, } EXPORT_SYMBOL_GPL(iomap_swapfile_activate); #endif /* CONFIG_SWAP */ + +static loff_t +iomap_bmap_actor(struct inode *inode, loff_t pos, loff_t length, + void *data, struct iomap *iomap) +{ + sector_t *bno = data, addr; + + if (iomap->type == IOMAP_MAPPED) { + addr = (pos - iomap->offset + iomap->addr) >> inode->i_blkbits; + if (addr > INT_MAX) + WARN(1, "would truncate bmap result\n"); + else + *bno = addr; + } + return 0; +} + +/* legacy ->bmap interface. 0 is the error return (!) */ +sector_t +iomap_bmap(struct address_space *mapping, sector_t bno, + const struct iomap_ops *ops) +{ + struct inode *inode = mapping->host; + loff_t pos = bno >> inode->i_blkbits; + unsigned blocksize = i_blocksize(inode); + + if (filemap_write_and_wait(mapping)) + return 0; + + bno = 0; + iomap_apply(inode, pos, blocksize, 0, ops, &bno, iomap_bmap_actor); + return bno; +} +EXPORT_SYMBOL_GPL(iomap_bmap); diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 819e0cd2a950..a044a824da85 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -4,6 +4,7 @@ #include +struct address_space; struct fiemap_extent_info; struct inode; struct iov_iter; @@ -100,6 +101,8 @@ loff_t iomap_seek_hole(struct inode *inode, loff_t offset, const struct iomap_ops *ops); loff_t iomap_seek_data(struct inode *inode, loff_t offset, const struct iomap_ops *ops); +sector_t iomap_bmap(struct address_space *mapping, sector_t bno, + const struct iomap_ops *ops); /* * Flags for direct I/O ->end_io: -- cgit v1.2.3-59-g8ed1b